Now, I've only beaten the second Mass Effect (multiple times), and started a playthrough on the first one and am about halfway through it. Bought the third game last week, don't really care about spoilers.
It has been very hard to play through the original Mass Effect, the gameplay in general is just very underwhelming and I just don't find the plot to be as good as its sequel. I do like the characters though, Kaidan, Ashley, Liara, and of course Tali. And the Mako.. it's just been very hard to get into the first title. I know why people like it, and I am still trudging forward, but it has not rubbed me the same way that its successor did.
I will say that Mass Effect 2 was an incredible game; after playing the original, it is clear to me that removing some of the 'rpg' parts of the game (all the customization in armor, weapons, etc.) was a very good thing. I find myself hindered having to change things constantly. I bought Mass Effect 2 on a whim, randomly decided to play the demo, it was on sale at Steam, and voila, bought just like that. The main storyline wasn't anything epic, but the characters were so good. There wasn't one unlikable member of the cast. My favorites being Miranda, Thane, Jack, and Samara, the inclusion of loyalty quests made the game - together with the last level, made the game a top-notch and a lasting effect on me.
Started Mass Effect 3, and it's been good and fun, more like 2 than 3, though I am a little disappointed in my favorites not being in my team. I just liked the ME2 team better, I guess, though I love having Kaidan and Liara again. We'll see how I feel towards the ending; after Final Fantasy XIII-2's ending, I'm pretty sure I can handle any kind of troll ending.